Dumbbell



FIG. 1 is a perspective view of a dumbbell showing my new design;

FIG. 2 is another perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a right side elevational view thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a bottom plan view thereof;

FIG. 9 is a perspective view of the dumbbell where the dumbbell is in a configuration of use; and,

FIG. 10 is an enlarged view of portion 10 shown in FIG. 1.

The broken lines in the drawings depict portions of the dumbbell that form no part of the claimed design. 

CLAIM The ornamental design for a dumbbell, as shown and described. 